Calculate the change in entropy of a large pail of water after 200 J of energy is reversibly transferred to the water at 20 $\circ$ C. A) -0.733 kJ.mol^-¹ B) +0.683 kJ.mol^-¹ C) -0.683 kJ.mol^-¹ D) +0.733 kJ.mol^-¹ E) -200 kJ.mol^-¹

Question

Quizplus · Accepted Answer

The change in entropy can be calculated using the formula:
ΔS = Q/T
where ΔS is the change in entropy, Q is the energy transferred, and T is the temperature in Kelvin.
Converting 20°C to Kelvin, we get:
T = 20°C + 273.15 = 293.15 K
Plugging in the values, we get:
ΔS = 200 J / 293.15 K = 0.6829 J/K
Rounding off to three significant figures and converting to the proper unit (J/K), we get:
ΔS = +0.683 J/K
Therefore, the best choice is B.

Calculate the Change in Entropy of a Large Pail of Water